Filters Panel

Trackpoint Filter
Selects the positions that build up the track
Fix type
No Fix: The device logged a position but did not have a fix. Usually unselected.
SPS: Standard Positioning Service. The accuracy of the signal may be degraded to 100 m via Selective Availability. S.A. was turned OFF on May 1st, 2000.
DGPS: Differential GPS.
Correction of the GPS coordinates by applying an offset identified by fixed position receivers. Supposed to be more precise when differential data is used.
PPS: Precise Positioning Service.
"Military" signal with high accuracy (< 10 m) - encryption only known to military
RTK: Real Time Kinematic.
Sat system used in RTK mode with fixed integers
FRTK: Float Real Time Kinematic.
Sat system used in RTK mode with floating integers
Estimate: The position is an estimation by the device. The position is usually not very precise. Also called 'dead reckoning'
Manual: Manual entry of the position. No known usage in the existing devices.
Sim: Simulator value. No known usage in existing devices.
Log Reason
Why the position was recorded.
Time: The time condition was reached. The previous position was logged more than the programmed number of seconds earlier.
Speed: The speed condition was reached. The speed was higher than the limit.
Distance: The distance conditions was reached. The measured distance was over the limit. This is not the direct line distance to the previous position!
Button: The position was logged because the user requested so by pressing the device button.
User *: Extra waypoint types can be logged through an application (like BT747). This list will be shortened later on. Currently selects the bit in the user field that has to be active.
Common Filter
Filter specification used for both waypoints and trackpoints.
Activate Common Filter When not active, the common filter is not used (and the menu items are grayed out.
*DOP: HDOP, VDOP and PDOP are related to the position accuracy. The smaller the value, the more accurate the position. It is recommended to log the HDOP value with each position and define the limit as 1.98.
HDOP: Horizontal precision
VDOP: Vertical precision.
PDOP: Positional precision.
rec nbr: Limits for the record number. This can help you to select only a part of the log.
distance: Limits for the distance field in a position record.
speed: Limits for the speed logged with a position.
NSAT: Minimum number of satelites in use needed. Also a method to select only precise positions (select at least 4 or 5 satellites)
Waypoint Filter
Select positions that will be used as waypoints - they are usually shown as icons with detailed position information.
The meaning of the filter settings is the same as for the trackpoint filter.